1. Field of the Invention
The invention generally relates to a foaminess characterization method for characterizing liquid foams and test substances and a foam generation method for generating the liquid foams.
2. Description of Related Art
Industry needs to determine degree of foaminess of liquid foams or defoaming effectiveness of defoamers in liquid foams for diverse applications such as, for example, soaps, detergents, foamable pharmaceutical and cosmetic compositions, paints, and coatings in order to evaluate quality thereof. A common industry measurement for this purpose is foam height of a liquid foam sample in a graduated cylinder. This method typically uses about 75 milliliters (mL) per sample and takes 15 minutes to 20 minutes per sample to measure initial height of foamable liquid in graduated cylinder, transfer foamable liquid to a container and vigorously stir sample therein, transfer stirred sample back to graduated cylinder and measure height of stirred sample. When this physical property measurement works well, foam height of the sample increases in proportion to increasing degree of foaming thereof.
United States Patent Application Publication Number US 2008/0166303 A1 mentions, among other things, a colored or colorable topical composition comprising: a) a foamable base composition comprising, 1) a flowable carrier composition; 2) a color agent; wherein the color agent is effective to impart, increase, or decrease or otherwise affect color of a foam produced from the foamable composition and wherein the color agent is one or more agents selected from the group consisting of a colored active agent, a colored indicator, a colored excipient, a pigment, a dye, a colorant and a coloring agent; b) a propellant at a concentration of about 3% to about 25% by weight of the total composition; wherein the base composition has a first color; and wherein the foam comprising the colored or colorable topical composition has a second color upon dispensing from an aerosol container, and wherein the first color and the second color are visually different. US 2008/0166303 A1 also mentions, among other things, a method of changing color and a use as a diagnostic.
There is a need in the art for an improved method of determining degree of foaminess of liquid foams or defoaming effectiveness of defoamers contained therein.